NATO
The North Atlantic Treaty Organization (NATO ; , OTAN), also called the North Atlantic Alliance, is an intergovernmental organization, intergovernmental Transnationalism, transnational military alliance of 32 Member states of NATO, member s ...
is a
military alliance
A military alliance is a formal Alliance, agreement between nations that specifies mutual obligations regarding national security. In the event a nation is attacked, members of the alliance are often obligated to come to their defense regardless ...
of
thirty-two European and North American countries that constitutes a system of
collective defense
Collective security is treaty, arrangement between states in which the institution accepts that an attack on one state is the concern of all and merits a collective response to threats by all. Collective security was a key principle underpinning ...
. The process of joining the alliance is governed by Article 10 of the
North Atlantic Treaty
The North Atlantic Treaty, also known as the Washington Treaty, forms the legal basis of, and is implemented by, the North Atlantic Treaty Organization (NATO). The treaty was signed in Washington, D.C., on 4 April 1949.
Background
The treat ...
, which allows for the invitation of "other European States" only and by subsequent agreements. Countries wishing to join must meet certain requirements and complete a multi-step process involving political dialogue and military integration. The accession process is overseen by the
North Atlantic Council, NATO's governing body. NATO was formed in 1949 with
twelve founding members and has added new members ten times. The first additions were
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
and
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
in 1952. In May 1955,
West Germany
West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...
joined NATO, which was one of the conditions agreed to as part of the end of the country's occupation by France, the United Kingdom, and the United States, prompting the Soviet Union to form its own collective security alliance (commonly called the
Warsaw Pact
The Warsaw Pact (WP), formally the Treaty of Friendship, Co-operation and Mutual Assistance (TFCMA), was a Collective security#Collective defense, collective defense treaty signed in Warsaw, Polish People's Republic, Poland, between the Sovi ...
) later that month. Following the end of the
Franco regime, newly democratic
Spain
Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
chose to join NATO in 1982.
In 1990, negotiators reached an agreement that a
reunified Germany would be in NATO under West Germany's existing membership. Following the
dissolution of the Soviet Union
The Soviet Union was formally dissolved as a sovereign state and subject of international law on 26 December 1991 by Declaration No. 142-N of the Soviet of the Republics of the Supreme Soviet of the Soviet Union. Declaration No. 142-Н of ...
in 1991, many former Warsaw Pact and
post-Soviet states
The post-Soviet states, also referred to as the former Soviet Union or the former Soviet republics, are the independent sovereign states that emerged/re-emerged from the dissolution of the Soviet Union in 1991. Prior to their independence, they ...
sought to join NATO.
Poland
Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...
,
Hungary
Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...
, and the
Czech Republic
The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...
became members in 1999, amid much debate within NATO itself. NATO then formalized the process of joining the organization with "Membership Action Plans", which aided the accession of seven
Central and Eastern Europe
Central and Eastern Europe is a geopolitical term encompassing the countries in Baltic region, Northeast Europe (primarily the Baltic states, Baltics), Central Europe (primarily the Visegrád Group), Eastern Europe, and Southeast Europe (primaril ...
countries shortly before the
2004 Istanbul summit:
Bulgaria
Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...
,
Estonia
Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Ru ...
,
Latvia
Latvia, officially the Republic of Latvia, is a country in the Baltic region of Northern Europe. It is one of the three Baltic states, along with Estonia to the north and Lithuania to the south. It borders Russia to the east and Belarus to t ...
,
Lithuania
Lithuania, officially the Republic of Lithuania, is a country in the Baltic region of Europe. It is one of three Baltic states and lies on the eastern shore of the Baltic Sea, bordered by Latvia to the north, Belarus to the east and south, P ...
,
Romania
Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...
,
Slovakia
Slovakia, officially the Slovak Republic, is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the west, and the Czech Republic to the northwest. Slovakia's m ...
, and
Slovenia
Slovenia, officially the Republic of Slovenia, is a country in Central Europe. It borders Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the south and southeast, and a short (46.6 km) coastline within the Adriati ...
. Two countries on the
Adriatic Sea
The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkans, Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Se ...
Albania
Albania ( ; or ), officially the Republic of Albania (), is a country in Southeast Europe. It is located in the Balkans, on the Adriatic Sea, Adriatic and Ionian Seas within the Mediterranean Sea, and shares land borders with Montenegro to ...
and
Croatia
Croatia, officially the Republic of Croatia, is a country in Central Europe, Central and Southeast Europe, on the coast of the Adriatic Sea. It borders Slovenia to the northwest, Hungary to the northeast, Serbia to the east, Bosnia and Herze ...
joined on 1 April 2009 before the
2009 Strasbourg–Kehl summit. The next member states to join NATO were
Montenegro
, image_flag = Flag of Montenegro.svg
, image_coat = Coat of arms of Montenegro.svg
, coa_size = 80
, national_motto =
, national_anthem = ()
, image_map = Europe-Mont ...
on 5 June 2017, and
North Macedonia
North Macedonia, officially the Republic of North Macedonia, is a landlocked country in Southeast Europe. It shares land borders with Greece to the south, Albania to the west, Bulgaria to the east, Kosovo to the northwest and Serbia to the n ...
on 27 March 2020.
Russia invaded Ukraine in 2022 after Russian president
Vladimir Putin
Vladimir Vladimirovich Putin (born 7 October 1952) is a Russian politician and former intelligence officer who has served as President of Russia since 2012, having previously served from 2000 to 2008. Putin also served as Prime Minister of Ru ...
claimed
"Claimed" is the eleventh episode of the The Walking Dead season 4, fourth season of the Apocalyptic and post-apocalyptic fiction, post-apocalyptic Horror fiction, horror television series ''The Walking Dead (TV series), The Walking Dead'', wh ...
that NATO military infrastructure was being built up inside
Ukraine
Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...
and that Ukraine's potential membership was a threat. Russia's invasion prompted
Finland
Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...
and
Sweden
Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...
to apply for NATO membership in May 2022.
Finland joined on 4 April 2023, the 74th anniversary of NATO's creation, and Sweden on 7 March 2024.
Ukraine applied for membership in September 2022 after Russia proclaimed
annexation of some of its territory.
Two other states have formally informed NATO of their membership aspirations:
Bosnia and Herzegovina
Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkans, Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to th ...
and
Georgia
Georgia most commonly refers to:
* Georgia (country), a country in the South Caucasus
* Georgia (U.S. state), a state in the southeastern United States
Georgia may also refer to:
People and fictional characters
* Georgia (name), a list of pe ...
.
Kosovo
Kosovo, officially the Republic of Kosovo, is a landlocked country in Southeast Europe with International recognition of Kosovo, partial diplomatic recognition. It is bordered by Albania to the southwest, Montenegro to the west, Serbia to the ...
also aspires to join.
Joining the alliance is a debated topic in several other European countries outside the alliance, including
Armenia
Armenia, officially the Republic of Armenia, is a landlocked country in the Armenian Highlands of West Asia. It is a part of the Caucasus region and is bordered by Turkey to the west, Georgia (country), Georgia to the north and Azerbaijan to ...
,
Austria
Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...
,
Cyprus
Cyprus (), officially the Republic of Cyprus, is an island country in the eastern Mediterranean Sea. Situated in West Asia, its cultural identity and geopolitical orientation are overwhelmingly Southeast European. Cyprus is the List of isl ...
,
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
,
Malta
Malta, officially the Republic of Malta, is an island country in Southern Europe located in the Mediterranean Sea, between Sicily and North Africa. It consists of an archipelago south of Italy, east of Tunisia, and north of Libya. The two ...
,
Moldova
Moldova, officially the Republic of Moldova, is a Landlocked country, landlocked country in Eastern Europe, with an area of and population of 2.42 million. Moldova is bordered by Romania to the west and Ukraine to the north, east, and south. ...
, and
Serbia
, image_flag = Flag of Serbia.svg
, national_motto =
, image_coat = Coat of arms of Serbia.svg
, national_anthem = ()
, image_map =
, map_caption = Location of Serbia (gree ...
.
Past enlargements
Cold War
Twelve countries were part of NATO at the time of its founding:
Belgium
Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...
,
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
,
Denmark
Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous a ...
,
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
,
Iceland
Iceland is a Nordic countries, Nordic island country between the Atlantic Ocean, North Atlantic and Arctic Oceans, on the Mid-Atlantic Ridge between North America and Europe. It is culturally and politically linked with Europe and is the regi ...
,
Italy
Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...
,
Luxembourg
Luxembourg, officially the Grand Duchy of Luxembourg, is a landlocked country in Western Europe. It is bordered by Belgium to the west and north, Germany to the east, and France on the south. Its capital and most populous city, Luxembour ...
,
the Netherlands
, Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...
,
Norway
Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ...
,
Portugal
Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...
, the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
, and the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
. The start of the
Cold War between 1947 and 1953 saw an ideological and economic divide between the capitalist states of Western Europe backed by United States with its
Marshall Plan and the
Truman Doctrine
The Truman Doctrine is a Foreign policy of the United States, U.S. foreign policy that pledges American support for democratic nations against Authoritarianism, authoritarian threats. The doctrine originated with the primary goal of countering ...
, and the communist states of Eastern Europe, backed by the
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
. As such, opposition to Soviet-style communism became a defining characteristic of the organization and the
anti-communist governments of
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
, which had just fought a
civil war
A civil war is a war between organized groups within the same Sovereign state, state (or country). The aim of one side may be to take control of the country or a region, to achieve independence for a region, or to change government policies.J ...
against a
pro-communist army, and
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
, whose newly-elected
Democrat Party were staunchly pro-American, came under internal and external pressure to join the alliance, which both did in February 1952.
The US, France, and the UK initially agreed to end
its occupation of Germany in May 1952 under the
Bonn–Paris conventions on the condition that the new Federal Republic of Germany, commonly called
West Germany
West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...
, would join NATO, because of concerns about allowing a non-aligned West Germany
to rearm. The allies also dismissed
Soviet proposals of a neutral-but-united Germany as insincere. France, however, delayed the start of the process, in part on the condition that a
referendum be held in Saar on its future status, and a revised treaty was signed on 23 October 1954, allowing the
North Atlantic Council to formally invite West Germany. Ratification of its membership was completed in May 1955. That month the Soviet Union established its own collective defense alliance, commonly called the
Warsaw Pact
The Warsaw Pact (WP), formally the Treaty of Friendship, Co-operation and Mutual Assistance (TFCMA), was a Collective security#Collective defense, collective defense treaty signed in Warsaw, Polish People's Republic, Poland, between the Sovi ...
, in part as a response to West German membership in NATO. In 1966, French president Charles de Gaulle announced the withdrawal of French forces from the integrated military structure of the NATO and ordered the removal of all foreign NATO forces from French territory. In 1974, Greece suspended its NATO membership over the
Turkish invasion of Cyprus
The Turkish invasion of Cyprus began on 20 July 1974 and progressed in two phases over the following month. Taking place upon a background of Cypriot intercommunal violence, intercommunal violence between Greek Cypriots, Greek and Turkish Cy ...
, but rejoined in 1980 with Turkey's cooperation.
Relations between NATO members and
Spain under dictator Francisco Franco were strained for many years, in large part because Franco had cooperated with the
Axis powers
The Axis powers, originally called the Rome–Berlin Axis and also Rome–Berlin–Tokyo Axis, was the military coalition which initiated World War II and fought against the Allies of World War II, Allies. Its principal members were Nazi Ge ...
during
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
. Though staunchly anti-communist,
Franco reportedly feared in 1955 that a Spanish application for NATO membership might be vetoed by its members at the time. Franco however did sign regular defense agreements with individual members, including the 1953
Pact of Madrid with the United States, which allowed their use of air and naval bases in Spain.
Following Franco's death in 1975,
Spain
Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
began a
transition to democracy, and came under international pressure to normalize relations with other western democracies. Prime Minister
Adolfo Suárez, first elected in 1976, proceeded carefully on relations with NATO because of divisions in
his coalition over the US's use of Spanish bases. In February 1981, following
a failed coup attempt,
Leopoldo Calvo-Sotelo became Prime Minister and campaigned strongly for NATO membership, in part to improve civilian control over the military, and Spain's NATO membership was approved in May 1982.
A
Spanish referendum in 1986 confirmed popular support for remaining in NATO.
During the mid-1980s the strength and cohesion of the Warsaw Pact, which had served as the main institution rivaling NATO, began to deteriorate. By 1989 the
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
was unable to stem the democratic and nationalist movements which were rapidly gaining ground.
Poland held multiparty elections in June 1989 that ousted the Soviet allied
Polish Workers' Party and the peaceful opening of the
Berlin Wall
The Berlin Wall (, ) was a guarded concrete Separation barrier, barrier that encircled West Berlin from 1961 to 1989, separating it from East Berlin and the East Germany, German Democratic Republic (GDR; East Germany). Construction of the B ...
that November symbolized the end of the Warsaw Pact as a way of enforcing Soviet control. The
fall of the Berlin Wall is recognized to be the end of the Cold War and ushered in a new period for Europe and NATO enlargement.
German reunification
Negotiations to
reunite East and West Germany took place throughout 1990, resulting in the signing of the
Two Plus Four Treaty in September 1990 and East Germany officially joining the Federal Republic of Germany on 1990. To secure Soviet approval of a united Germany remaining in NATO, the treaty prohibited foreign troops and nuclear weapons from being stationed in the former East Germany,
though an addendum signed by all parties specified that foreign NATO troops could be deployed east of the Cold War line after the Soviet departure at the discretion of the government of a united Germany, permitting NATO's enlargement to the east. There is no mention of NATO expansion into any other country in the September–October 1990 agreements on German reunification.
Whether or not representatives from NATO member states informally committed to not enlarge NATO into other parts of Eastern Europe during these and contemporary negotiations with Soviet counterparts has long been a matter of dispute among historians and international relations scholars.
With several countries threatening to withdraw from the
Warsaw Pact
The Warsaw Pact (WP), formally the Treaty of Friendship, Co-operation and Mutual Assistance (TFCMA), was a Collective security#Collective defense, collective defense treaty signed in Warsaw, Polish People's Republic, Poland, between the Sovi ...
, the Soviet military relinquished control of the organization in March 1991, allowing it to be formally dissolved that July.
The so-called "
parade of sovereignties
The parade of sovereignties () was a series of declarations of sovereignty of various degrees by the republics of the Soviet Union and autonomous units within the republics ( autonomous republics, autonomous oblasts and autonomous okrugs) from ...
" declared by republics in the Baltic and Caucasus regions of the Soviet Union and their
War of Laws with the government in
Moscow
Moscow is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia, standing on the Moskva (river), Moskva River in Central Russia. It has a population estimated at over 13 million residents with ...
further fractured its cohesion. Following the failure of the
New Union Treaty, the leadership of the remaining constituent republics of the Soviet Union, starting with
Ukraine in August 1991, declared their independence and initiated the
dissolution of the Soviet Union
The Soviet Union was formally dissolved as a sovereign state and subject of international law on 26 December 1991 by Declaration No. 142-N of the Soviet of the Republics of the Supreme Soviet of the Soviet Union. Declaration No. 142-Н of ...
, which was completed in December of that year.
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
, led by President
Boris Yeltsin
Boris Nikolayevich Yeltsin (1 February 1931 – 23 April 2007) was a Soviet and Russian politician and statesman who served as President of Russia from 1991 to 1999. He was a member of the Communist Party of the Soviet Union (CPSU) from 1961 to ...
, became the most prominent of the independent states. The Westernization trend of many former Soviet allied states led them to privatize their economies and formalize their relationships with NATO countries, the first step for many towards European integration and possible NATO membership.
By August 1993, Polish President
Lech Wałęsa
Lech Wałęsa (; ; born 29 September 1943) is a Polish statesman, dissident, and Nobel Peace Prize laureate who served as the president of Poland between 1990 and 1995. After winning the 1990 Polish presidential election, 1990 election, Wałę ...
was actively campaigning for his country to join NATO, at which time Yeltsin reportedly told him that Russia did not perceive its membership in NATO as a threat to his country. Yeltsin however retracted this informal declaration the following month, writing that expansion "would violate the spirit of the treaty on the final settlement", which "precludes the option of expanding the NATO zone into the East."
During one of
James Baker's 1990 talks with Soviet leader
Mikhail Gorbachev
Mikhail Sergeyevich Gorbachev (2 March 1931 – 30 August 2022) was a Soviet and Russian politician who served as the last leader of the Soviet Union from 1985 to dissolution of the Soviet Union, the country's dissolution in 1991. He served a ...
, Baker did suggest that the German reunification negotiations could have resulted in an agreement whereby "there would be no extension of NATO's jurisdiction for forces of NATO one inch to the east," and historians like Mark Kramer have interpreted it as applying, at least in certain Soviet representatives' understanding, to all of Eastern Europe.
Gorbachev later stated that NATO expansion was "not discussed at all" in 1990, but, like Yeltsin, described the expansion of NATO past East Germany as "a violation of the spirit of the statements and assurances made to us in 1990."
This view, that informal assurances were given by diplomats from NATO members to the Soviet Union in 1990, is common in countries like Russia,
and, according to political scientist
Marc Trachtenberg, available evidence suggests that allegations made since by Russian leadership about the existence of such assurances "were by no means baseless."
Yeltsin was succeeded in 2000 by
Vladimir Putin
Vladimir Vladimirovich Putin (born 7 October 1952) is a Russian politician and former intelligence officer who has served as President of Russia since 2012, having previously served from 2000 to 2008. Putin also served as Prime Minister of Ru ...
, who further promoted the idea that guarantees about enlargement were made in 1990, including during
a 2007 speech in Munich.
This impression was later used by him as part of his justification for
Russia's 2014 actions in Ukraine and the
Russian invasion of Ukraine in 2022.
Visegrád Group
In February 1991, Poland, Hungary, and Czechoslovakia formed the
Visegrád Group to push for
European integration under the
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
and NATO, as well as to conduct military reforms in line with NATO standards. Internal NATO reaction to these former
Warsaw Pact
The Warsaw Pact (WP), formally the Treaty of Friendship, Co-operation and Mutual Assistance (TFCMA), was a Collective security#Collective defense, collective defense treaty signed in Warsaw, Polish People's Republic, Poland, between the Sovi ...
countries was initially negative, but by the
1991 Rome summit in November, members agreed to a series of goals that could lead to accession, such as market and democratic liberalization, and that NATO should be a partner in these efforts. Debate within the American government as to whether enlargement of NATO was feasible or desirable began during the
George H.W. Bush administration.
By mid-1992, a consensus emerged within the administration that NATO enlargement was a wise
realpolitik measure to strengthen Euro-American hegemony.
In the absence of NATO enlargement, Bush administration officials worried that the European Union might fill the security vacuum in
Central Europe
Central Europe is a geographical region of Europe between Eastern Europe, Eastern, Southern Europe, Southern, Western Europe, Western and Northern Europe, Northern Europe. Central Europe is known for its cultural diversity; however, countries in ...
, and thus challenge American post-Cold War influence.
There was further debate during the
presidency of Bill Clinton
Bill Clinton's tenure as the 42nd president of the United States began with his first inauguration on January 20, 1993, and ended on January 20, 2001. Clinton, a Democrat from Arkansas, took office following his victory over Republican in ...
between a rapid offer of full membership to several select countries versus a slower, more limited membership to a wide range of states over a longer time span. Victory by the Republican Party, which advocated for aggressive expansion, in the
1994 US congressional election helped sway US policy in favor of wider full-membership enlargement, which the US ultimately pursued in the following years. In 1996, Clinton called for former Warsaw Pact countries and post-Soviet republics to join NATO, and made NATO enlargement a part of his foreign policy.
That year, Russian leaders like Foreign Minister
Andrei Kozyrev indicated their country's opposition to NATO enlargement. While Russian President Boris Yeltsin did sign
an agreement with NATO in May 1997 that included text referring to new membership, he clearly described NATO expansion as "unacceptable" and a threat to Russian security in his December 1997 National Security Blueprint. Russian military actions, including the
First Chechen War
The First Chechen War, also referred to as the First Russo-Chechen War, was a struggle for independence waged by the Chechen Republic of Ichkeria against the invading Russia, Russian Federation from 1994 to 1996. After a mutually agreed on treaty ...
, were among the factors driving
Central and Eastern Europe
Central and Eastern Europe is a geopolitical term encompassing the countries in Baltic region, Northeast Europe (primarily the Baltic states, Baltics), Central Europe (primarily the Visegrád Group), Eastern Europe, and Southeast Europe (primaril ...
an countries, particularly those with memories of similar Soviet offensives, to push for NATO application and ensure their long-term security. Political parties reluctant to move on NATO membership were voted out of office, including the
Bulgarian Socialist Party in 1997 and Slovak
HZDS in 1998. Hungary's interest in joining was confirmed by a
November 1997 referendum that returned 85.3% in favor of membership. During this period, wider forums for regional cooperation between NATO and its eastern neighbors were set up, including the
North Atlantic Cooperation Council (later the
Euro-Atlantic Partnership Council
The Euro-Atlantic Partnership Council (EAPC) is a post–Cold War, North Atlantic Treaty Organization (NATO) institution. The EAPC is a multilateral forum created to improve relations between NATO and non-NATO countries in Europe and Central Asi ...
) and the
Partnership for Peace.
While the other Visegrád members were invited to join NATO at its
1997 Madrid summit, Slovakia was excluded based on what several members considered undemocratic actions by nationalist Prime Minister
Vladimír Mečiar.
Romania
Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...
and
Slovenia
Slovenia, officially the Republic of Slovenia, is a country in Central Europe. It borders Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the south and southeast, and a short (46.6 km) coastline within the Adriati ...
were both considered for invitation in 1997, and each had the backing of a prominent NATO member, France and Italy respectively, but support for this enlargement was not unanimous between members, nor within individual governments, including in the
US Congress
The United States Congress is the legislature, legislative branch of the federal government of the United States. It is a Bicameralism, bicameral legislature, including a Lower house, lower body, the United States House of Representatives, ...
. In an open letter to US President
Bill Clinton
William Jefferson Clinton (né Blythe III; born August 19, 1946) is an American politician and lawyer who was the 42nd president of the United States from 1993 to 2001. A member of the Democratic Party (United States), Democratic Party, ...
, more than forty foreign policy experts including
Bill Bradley,
Sam Nunn,
Gary Hart,
Paul Nitze, and
Robert McNamara
Robert Strange McNamara (; June 9, 1916 – July 6, 2009) was an American businessman and government official who served as the eighth United States secretary of defense from 1961 to 1968 under presidents John F. Kennedy and Lyndon B. Johnson ...
expressed their concerns about NATO expansion as both expensive and unnecessary given the lack of an external threat from Russia at that time. Hungary, Poland, and the Czech Republic officially joined NATO in March 1999.
Vilnius Group
At the
1999 Washington summit NATO issued new guidelines for membership with individualized "
Membership Action Plans" for
Albania
Albania ( ; or ), officially the Republic of Albania (), is a country in Southeast Europe. It is located in the Balkans, on the Adriatic Sea, Adriatic and Ionian Seas within the Mediterranean Sea, and shares land borders with Montenegro to ...
,
Bulgaria
Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...
,
Estonia
Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Ru ...
,
Latvia
Latvia, officially the Republic of Latvia, is a country in the Baltic region of Northern Europe. It is one of the three Baltic states, along with Estonia to the north and Lithuania to the south. It borders Russia to the east and Belarus to t ...
,
Lithuania
Lithuania, officially the Republic of Lithuania, is a country in the Baltic region of Europe. It is one of three Baltic states and lies on the eastern shore of the Baltic Sea, bordered by Latvia to the north, Belarus to the east and south, P ...
,
North Macedonia
North Macedonia, officially the Republic of North Macedonia, is a landlocked country in Southeast Europe. It shares land borders with Greece to the south, Albania to the west, Bulgaria to the east, Kosovo to the northwest and Serbia to the n ...
, Romania, Slovakia, and Slovenia in order to standardize the process for new members. In May 2000, these countries joined with
Croatia
Croatia, officially the Republic of Croatia, is a country in Central Europe, Central and Southeast Europe, on the coast of the Adriatic Sea. It borders Slovenia to the northwest, Hungary to the northeast, Serbia to the east, Bosnia and Herze ...
to form the
Vilnius Group in order to cooperate and lobby for common NATO membership, and by the
2002 Prague summit seven were invited for membership, which took place at the
2004 Istanbul summit.
Slovenia had held
a referendum on NATO the previous year, with 66% approving of membership.
Russia was particularly upset with the addition of the three
Baltic states
The Baltic states or the Baltic countries is a geopolitical term encompassing Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, and the OECD. The three sovereign states on the eastern co ...
, the first countries that were part of the Soviet Union to join NATO.
Russian troops had been stationed in Baltic states as late as 1995,
but the goals of European integration and NATO membership were very attractive for the Baltic states. Rapid investments in their own armed forces showed a seriousness in their desire for membership, and participation in NATO-led post-9/11 operations, particularly by Estonia in Afghanistan, won the three countries key support from individuals like US Senator
John McCain
John Sidney McCain III (August 29, 1936 – August 25, 2018) was an American statesman and United States Navy, naval officer who represented the Arizona, state of Arizona in United States Congress, Congress for over 35 years, first as ...
, French President
Jacques Chirac
Jacques René Chirac (, ; ; 29 November 193226 September 2019) was a French politician who served as President of France from 1995 to 2007. He was previously Prime Minister of France from 1974 to 1976 and 1986 to 1988, as well as Mayor of Pari ...
, and German Chancellor
Gerhard Schröder
Gerhard Fritz Kurt Schröder (; born 7 April 1944) is a German former politician and Lobbying, lobbyist who served as Chancellor of Germany from 1998 to 2005. From 1999 to 2004, he was also the Leader of the Social Democratic Party of Germany (S ...
.
A 2006 study in the journal ''
Security Studies
__NOTOC__
Security studies, also known as international security studies, is an academic sub-field within the wider discipline of international relations that studies organized violence, military conflict, national security, and international s ...
'' argued that the NATO enlargements in 1999 and 2004 contributed to democratic consolidation in Central and Eastern Europe.
Adriatic Charter
Croatia also started a Membership Action Plan at the 2002 summit, but was not included in the 2004 enlargement. In May 2003, it joined with
Albania
Albania ( ; or ), officially the Republic of Albania (), is a country in Southeast Europe. It is located in the Balkans, on the Adriatic Sea, Adriatic and Ionian Seas within the Mediterranean Sea, and shares land borders with Montenegro to ...
and Macedonia to form the
Adriatic Charter to support each other in their pursuit of membership. Croatia's prospect of membership sparked a national debate on whether a referendum on NATO membership needed to be held before joining the organization. Croatian Prime Minister
Ivo Sanader ultimately agreed in January 2008, as part of forming a coalition government with the
HSS and
HSLS parties, not to officially propose one. Albania and Croatia were invited to join NATO at the
2008 Bucharest summit that April, though Slovenia threatened to hold up Croatian membership over
their border dispute in the
Bay of Piran. Slovenia did ratify Croatia's accession protocol in February 2009, before Croatia and Albania both officially joined NATO just before the
2009 Strasbourg–Kehl summit, with little opposition from Russia.
Montenegro
, image_flag = Flag of Montenegro.svg
, image_coat = Coat of arms of Montenegro.svg
, coa_size = 80
, national_motto =
, national_anthem = ()
, image_map = Europe-Mont ...
declared independence on 3 June 2006; the new country subsequently joined the Partnership for Peace program at the
2006 Riga summit and then applied for a Membership Action Plan on 5 November 2008, which was granted in December 2009. Montenegro also began full membership with the Adriatic Charter of NATO aspirants in May 2009. NATO formally invited Montenegro to join the alliance on 2 December 2015, with negotiations concluding in May 2016; Montenegro joined NATO on 5 June 2017.
Macedonia joined the
Partnership for Peace in 1995, and commenced its
Membership Action Plan in 1999, at the same time as
Albania
Albania ( ; or ), officially the Republic of Albania (), is a country in Southeast Europe. It is located in the Balkans, on the Adriatic Sea, Adriatic and Ionian Seas within the Mediterranean Sea, and shares land borders with Montenegro to ...
. At the
2008 Bucharest summit,
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
blocked a proposed invitation because it believed that the official name it was using at the time, "Republic of Macedonia," implied territorial aspirations toward its own region of
Greek Macedonia. NATO nations agreed that the country would receive an invitation upon resolution of the
Macedonia naming dispute
The use of the country name "Macedonia (terminology), Macedonia" was disputed between Greece and the North Macedonia, Republic of Macedonia (now North Macedonia) between 1991 and 2019. The dispute was a source of instability in the Balkans#W ...
. Macedonia sued Greece at the
International Court of Justice
The International Court of Justice (ICJ; , CIJ), or colloquially the World Court, is the only international court that Adjudication, adjudicates general disputes between nations, and gives advisory opinions on International law, internation ...
(ICJ) over Greece's veto of Macedonia's NATO membership. Macedonia was part of the
Vilnius Group, and had formed the
Adriatic Charter with Croatia and Albania in 2003 to better coordinate NATO accession.
In June 2017, Macedonian Prime Minister
Zoran Zaev signaled he would consider alternative names for the country in order to strike a compromise with Greece, settle the naming dispute and lift Greek objections to Macedonia joining the alliance. The naming dispute was resolved with the
Prespa Agreement in June 2018 under which the country adopted the name North Macedonia, which was supported by
a referendum in September 2018. NATO invited North Macedonia to begin membership talks on 11 July 2018; formal accession talks began on 18 October 2018. NATO's members signed North Macedonia's accession protocol on 6 February 2019. Most countries ratified the accession treaty in 2019, with
Spain
Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
ratifying its accession protocol in March 2020. The
Sobranie also ratified the treaty unanimously on 11 February 2020, before North Macedonia became a NATO member state on 27 March 2020.
Finland and Sweden
In 1949,
Sweden
Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...
chose not to join NATO and declared a security policy aiming for
non-alignment in peace and neutrality in war. This position was maintained without much discussion during the
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
. During this time,
Finland
Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...
's relationship with NATO and the Soviet Union followed the
Paasikivi–Kekkonen doctrine, whereby the country joined neither the Western nor Eastern blocs. Following the
dissolution of the Soviet Union
The Soviet Union was formally dissolved as a sovereign state and subject of international law on 26 December 1991 by Declaration No. 142-N of the Soviet of the Republics of the Supreme Soviet of the Soviet Union. Declaration No. 142-Н of ...
in 1991, both countries joined NATO's
Partnership for Peace in 1994 and provided peacekeeping forces to various NATO missions, including Kosovo (Kosovo Force, KFOR) and Afghanistan (International Security Assistance Force, ISAF) in the early 2000s.
Annexation of Crimea by the Russian Federation, Russia's annexation of Crimea from Ukraine in 2014 and subsequent full-scale Russian invasion of Ukraine, invasion of Ukraine in 2022 led both countries to revisit their security and defence policies. Opinion polls in both countries shortly after the 2022 invasion for the first time showed clear majorities supported joining NATO. The major political parties in both also re-evaluated their positions on NATO membership, with many moving to either support membership or drop long-standing opposition. On 15 May 2022, Finland's Prime Minister Sanna Marin, Marin and President Sauli Niinistö, Niinistö together announced that Finland would apply for NATO membership, while Swedish Prime Minister of Sweden, Prime Minister Magdalena Andersson announced that Sweden would do the same the following day. Formal applications for membership were jointly submitted by both countries on 18 May 2022.
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
, however, opposed the start of accession negotiations for Finland and Sweden over multiple issues, most notably their claim that Finland and Sweden supported the Kurds, Kurdish groups like the Kurdistan Workers' Party, PKK, Democratic Union Party (Syria), PYD, and People's Defense Units, YPG, which Turkey views as terrorists,
and the followers of Fethullah Gülen, whom Turkey accused of orchestrating the unsuccessful 2016 Turkish coup d'état attempt.
Accession negotiations only began following the signing of a tripartite memorandum between Finland, Sweden, and Turkey during the 2022 Madrid summit, NATO summit in Madrid in June 2022. That memorandum allowed for formal invitations and for the ratification process to begin the following month,
and by that October, only
Hungary
Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...
and Turkey had not approved the pair's applications.
Negotiations between the countries continued, and in February 2023, Turkish President Recep Tayyip Erdoğan announced that he now had a positive view of Finland's membership, but still a negative view of Sweden's. After the National Assembly (Hungary), Hungarian and Grand National Assembly of Turkey, Turkish parliaments both approved Finland's application in March, Finland became a member of the alliance on 4 April 2023, the 74th anniversary of the
North Atlantic Treaty
The North Atlantic Treaty, also known as the Washington Treaty, forms the legal basis of, and is implemented by, the North Atlantic Treaty Organization (NATO). The treaty was signed in Washington, D.C., on 4 April 1949.
Background
The treat ...
being signed. Turkey and Sweden finally came to an understanding in early 2024, allowing Sweden to become the 32nd member of the alliance on 7 March 2024.
According to the Russian defence minister Sergei Shoigu, Finland's accession to NATO significantly increased the risk of a wider conflict in Europe. The move doubled the length of the border that the North Atlantic Treaty Organization shares with Russia. Russian President
Vladimir Putin
Vladimir Vladimirovich Putin (born 7 October 1952) is a Russian politician and former intelligence officer who has served as President of Russia since 2012, having previously served from 2000 to 2008. Putin also served as Prime Minister of Ru ...
, however, has consistently dismissed Finland's and Sweden's accession to NATO,
stating it poses "no threat to Russia".
Summary table and map
Criteria and process
Article 10 and the Open Door Policy
The
North Atlantic Treaty
The North Atlantic Treaty, also known as the Washington Treaty, forms the legal basis of, and is implemented by, the North Atlantic Treaty Organization (NATO). The treaty was signed in Washington, D.C., on 4 April 1949.
Background
The treat ...
is the basis of the organization, and, as such, any changes including new membership requires ratification by all current signers of the treaty. The treaty's Article 10 describes how non-member states may join
NATO
The North Atlantic Treaty Organization (NATO ; , OTAN), also called the North Atlantic Alliance, is an intergovernmental organization, intergovernmental Transnationalism, transnational military alliance of 32 Member states of NATO, member s ...
:
Article 10 poses two general limits to non-member states. First, only European states are eligible for new membership, and second, these states not only need the approval of all the existing member states, but every member state can put some criteria forward that have to be attained. In practice, NATO formulates a common set of criteria. However, for instance,
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
blocked the Republic of Macedonia's accession to NATO for many years because it Macedonia naming dispute, disagreed with the use of the name Macedonia. Turkey similarly opposes the participation of the Republic of Cyprus with NATO institutions as long as the Cyprus dispute is not resolved.
Since the
1991 Rome summit, when the delegations of its member states officially offered cooperation with Europe's newly democratic states, NATO has addressed and further defined the expectations and procedure for adding new members. The 1994 Brussels summit#Accomplishments, 1994 Brussels Declaration reaffirmed the principles in Article 10 and led to the "Study on NATO Enlargement". Published in September 1995, the study outlined the "how and why" of possible enlargement in Europe,
highlighting three principles from the 1949 treaty for members to have: "democracy, individual liberty, and rule of law".
As NATO Secretary General Willy Claes noted, the 1995 study did not specify the "who or when," though it discussed how the then newly formed
Partnership for Peace and
North Atlantic Cooperation Council could assist in the enlargement process, and noted that on-going territorial disputes could be an issue for whether a country was invited. At the
1997 Madrid summit, the heads of state of NATO issued the "Madrid Declaration on Euro-Atlantic Security and Cooperation" which invited three
Central Europe
Central Europe is a geographical region of Europe between Eastern Europe, Eastern, Southern Europe, Southern, Western Europe, Western and Northern Europe, Northern Europe. Central Europe is known for its cultural diversity; however, countries in ...
an countries to join the alliance, out of the twelve that had at that point requested to join, laying out a path for others to follow.
The text of Article 10 was the origin for the April 1999 statement of a "NATO open door policy".
In practice, diplomats and officials have stated that having no territorial disputes is a prerequisite to joining NATO, as a member with such a dispute would be automatically considered under attack by the occupying entity. However,
West Germany
West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...
joined NATO in 1955 despite having territorial disputes with East Germany and other states until the early 1970s.
Membership Action Plan
The biggest step in the formalization of the process for inviting new members came at the
1999 Washington summit when the Membership Action Plan (MAP) mechanism was approved as a stage for the current members to regularly review the formal applications of aspiring members. A country's participation in MAP entails the annual presentation of reports concerning its progress on five different measures:
* Willingness to settle international, ethnic or external territorial disputes by peaceful means, commitment to the rule of law and human rights, and democratic control of armed forces
* Ability to contribute to the organization's defense and missions
* Devotion of sufficient resources to armed forces to be able to meet the commitments of membership
* Security of sensitive information, and safeguards ensuring it
* Compatibility of domestic legislation with NATO cooperation
NATO provides feedback as well as technical advice to each country and evaluates its progress on an individual basis.
Once members agree that a country meets the requirements, NATO can issue that country an invitation to begin accession talks. The final accession process, once invited, involves five steps leading up to the signing of the accession protocols and the acceptance and ratification of those protocols by the governments of the current NATO members.
In November 2002, NATO invited seven countries to join it via the MAP: Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia. All seven invitees joined in March 2004, which was observed at a flag-raising ceremony on 2 April. After that date, NATO numbered 26 allies. Other former MAP participants were Albania–NATO relations, Albania and Croatia–NATO relations, Croatia between May 2002 and April 2009, Montenegro–NATO relations, Montenegro between December 2009 and June 2017, and North Macedonia–NATO relations, North Macedonia between April 1999 and March 2020, when it joined NATO. ,
Bosnia and Herzegovina
Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkans, Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to th ...
is the only country participating in a MAP.
Intensified dialogue
Intensified Dialogue was first introduced in April 2005 at an informal meeting of foreign ministers in Vilnius, Lithuania, as a response to Ukrainian aspirations for NATO membership and related reforms taking place under President Viktor Yushchenko, and which followed the 2002 signing of the NATO–Ukraine Action Plan under his predecessor, Leonid Kuchma.
This formula, which includes discussion of a "full range of political, military, financial and security issues relating to possible NATO membership ... had its roots in the
1997 Madrid summit", where the participants had agreed "to continue the Alliance's intensified dialogs with those nations that aspire to NATO membership or that otherwise wish to pursue a dialog with NATO on membership questions".
In September 2006,
Georgia
Georgia most commonly refers to:
* Georgia (country), a country in the South Caucasus
* Georgia (U.S. state), a state in the southeastern United States
Georgia may also refer to:
People and fictional characters
* Georgia (name), a list of pe ...
became the second to be offered the Intensified Dialogue status, following a rapid change in foreign policy under President Mikhail Saakashvili and what it perceived as a demonstration of military readiness during the 2006 Kodori crisis.
Montenegro
, image_flag = Flag of Montenegro.svg
, image_coat = Coat of arms of Montenegro.svg
, coa_size = 80
, national_motto =
, national_anthem = ()
, image_map = Europe-Mont ...
,
Bosnia and Herzegovina
Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkans, Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to th ...
, and
Serbia
, image_flag = Flag of Serbia.svg
, national_motto =
, image_coat = Coat of arms of Serbia.svg
, national_anthem = ()
, image_map =
, map_caption = Location of Serbia (gree ...
similarly received offers at the April
2008 Bucharest summit. While its neighbors both requested and accepted the dialog program, Serbia's offer was presented to guarantee the possibility of future ties with the alliance.
Aspiring members

, three states have formally expressed their desire to join NATO. Bosnia and Herzegovina is the only country with a
Membership Action Plan, which together with Georgia, were named NATO "aspirant countries" at the North Atlantic Council meeting on 7 December 2011. During the 2008 Bucharest summit, 2008 NATO summit held in Bucharest and against the urging of United States President George W. Bush, Georgia's and Ukraine's accessions into NATO were blocked by Nicolas Sarkozy-led France, and by Angela Merkel-led Germany, which based its decision upon Germany maintaining its dependence upon hydrocarbons from
Vladimir Putin
Vladimir Vladimirovich Putin (born 7 October 1952) is a Russian politician and former intelligence officer who has served as President of Russia since 2012, having previously served from 2000 to 2008. Putin also served as Prime Minister of Ru ...
-led Russia. Ukraine was recognized as an aspirant country after the Revolution of Dignity, 2014 Ukrainian revolution, and formally applied for membership in 2022 following its Russian invasion of Ukraine, invasion by Russia.
Bosnia and Herzegovina
The Operation Deliberate Force, 1995 NATO bombing of Bosnia and Herzegovina targeted the Army of Republika Srpska, Bosnian Serb Army and together with international pressure led to the resolution of the Bosnian War and the signing of the Dayton Agreement in 1995. Since then, NATO has led the Implementation Force and Stabilisation Force in Bosnia and Herzegovina, Stabilization Force, and other peacekeeping efforts in the country. Bosnia and Herzegovina joined the Partnership for Peace in 2006, and signed an agreement on security cooperation in March 2007. Bosnia and Herzegovina began further cooperation with NATO within its Individual Partnership Action Plan in January 2008.
The country then started the process of Intensified Dialogue at the
2008 Bucharest summit.
The country was invited to join the
Adriatic Charter of NATO aspirants in September 2008.
The Federation of Bosnia and Herzegovina within
Bosnia and Herzegovina
Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkans, Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to th ...
has expressed willingness to join NATO, however, it faces consistent political pressure from Republika Srpska, the other political entity in the country, alongside its partners in
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
. On 2 October 2009, Haris Silajdžić, the Bosniak Member of the Presidency, announced official application for
Membership Action Plan. On 22 April 2010, NATO agreed to launch the
Membership Action Plan for Bosnia and Herzegovina, but with certain conditions attached.
Turkey is thought to be the biggest supporter of Bosnian membership, and heavily influenced the decision.
The conditions of the MAP, however, stipulated that no Annual National Programme could be launched until 63 military facilities are transferred from Political divisions of Bosnia and Herzegovina, Bosnia's political divisions to the central government, which is one of the conditions for the High Representative for Bosnia and Herzegovina#Conditions for closure of the Office of the High Representative, OHR closure. The leadership of the Republika Srpska has opposed this transfer as a loss of autonomy. All movable property, including all weapons and other army equipment, is fully registered as the property of the country starting 1 January 2006. A ruling of the Constitutional Court of Bosnia and Herzegovina on 6 August 2017 decided that a disputed military facility in Han Pijesak is to be registered as property of Bosnia and Herzegovina. Despite the fact that all immovable property is not fully registered, NATO approved the activation of the
Membership Action Plan for Bosnia and Herzegovina, and called on Bosnia to submit an Annual National Programme on 5 December 2018.
A February 2017 poll showed that 59% of the country supports NATO membership, but results were very divided depending on ethnic groups. While 84% of those who identified as Bosniak or Croats of Bosnia and Herzegovina, Croat supported NATO membership, only 9% of those who identified as Serbs of Bosnia and Herzegovina, Serb did. Bosnian chances of joining NATO may depend on Serbia's attitude towards the alliance, since the leadership of Republika Srpska might be reluctant to go against Serbian interests. In October 2017, the National Assembly (Republika Srpska), National Assembly of the Republika Srpska passed a nonbinding resolution opposing NATO membership for Bosnia and Herzegovina. On 2 March 2022, Vjosa Osmani, the President of Kosovo, called on NATO to speed up the membership process for Kosovo and Bosnia and Herzegovina. Osmani also criticized Aleksandar Vučić, the President of Serbia, accusing him of using Milorad Dodik to "destroy the unity of Bosnia and Herzegovina".
Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...
's relationship with NATO has been politically divisive, and is part of a larger debate over Ukraine's ties to both the European Union and Russia. Ukraine established ties to the alliance with a NATO–Ukraine Action Plan in November 2002,
joined NATO's
Partnership for Peace in February 2005, then entered into the Intensified Dialogue program with NATO in April 2005.
The position of Russian leaders on Ukraine–NATO relations, Ukraine-NATO relations has changed over time. In 2002, Russia's president
Vladimir Putin
Vladimir Vladimirovich Putin (born 7 October 1952) is a Russian politician and former intelligence officer who has served as President of Russia since 2012, having previously served from 2000 to 2008. Putin also served as Prime Minister of Ru ...
declared no objections to Ukraine's growing relations with NATO, saying it was a matter for Ukraine and NATO. From 2008, Russia began stating its opposition to Ukraine's membership. That March, Ukraine applied for a
Membership Action Plan (MAP), the first step in joining NATO. At the April
2008 Bucharest summit, NATO Secretary General Jaap de Hoop Scheffer declared that Ukraine and Georgia would someday join NATO, but neither would begin Membership Action Plans. At this summit, Putin called Ukrainian membership "a direct threat".
When Viktor Yanukovych became Ukraine's president in 2010, he said that Ukraine would remain a "European, non-aligned state", and would remain a member of NATO's outreach program. In June 2010 the Verkhovna Rada, Ukrainian parliament voted to drop the goal of NATO membership, in a bill drafted by Yanukovych. This affirmed Ukraine's neutral status and forbade its membership in any military bloc, but allowed for co-operation with alliances such as NATO.

In the February 2014 Revolution of Dignity, Ukrainian Revolution, Ukraine's parliament voted to remove Yanukovych. Soon after, while Ukraine was still a neutral country, Russia Russian occupation of Crimea, occupied and Annexation of Crimea by the Russian Federation, annexed Crimea. The following month, new Prime Minister Arseniy Yatsenyuk said Ukraine was not seeking NATO membership.
In August 2014, the Russian military War in Donbas#August 2014 invasion by Russian forces, invaded eastern Ukraine to support its Russian separatist forces in Ukraine, separatist proxies. Because of this, Yatsenyuk announced the resumption of the NATO membership bid, and in December 2014, Ukraine's parliament voted to drop non-aligned status. NATO Secretary General Anders Fogh Rasmussen said membership was still an option. Support for membership rose to 64 percent in government-held Ukraine according to a July 2015 poll, and polls showed that the rise in support for NATO was linked to Russia's ongoing military intervention.
In June 2017, Ukraine's parliament passed a law making NATO integration a foreign policy priority, and President Petro Poroshenko announced he would negotiate a
Membership Action Plan. Ukraine was acknowledged as an aspiring member by March 2018. In September 2018, Ukraine's parliament voted to include the goal of NATO membership in the constitution.
During 2021, there were massive Prelude to the Russian invasion of Ukraine, Russian military build-ups near Ukraine's borders. In April 2021, President Volodymyr Zelenskyy said that NATO membership "is the only way to end the war in Donbas" and that a MAP "will be a real signal for Russia". Putin demanded that Ukraine be barred from ever joining NATO. Secretary General Jens Stoltenberg replied that Ukraine's relationship with NATO are a matter for Ukraine and NATO, adding that "Russia has no right to establish a sphere of influence to try to control their neighbors". Stoltenberg stated that Putin "actually sent a draft treaty that they wanted NATO to sign, to promise no more NATO enlargement. That was what he sent us. And was a pre-condition for not invade Ukraine. Of course we didn't sign that".
Russia invaded Ukraine in February 2022. In his On conducting a special military operation, speech announcing the invasion, Putin Disinformation in the Russian invasion of Ukraine#Allegations of NATO aggression, falsely claimed that NATO military infrastructure was being built up inside Ukraine, threatening Russia. Russia's invasion drove Finland and Sweden to apply for NATO membership. In June 2022, Putin said their membership wasn't a problem for Russia, but Ukraine's membership is a "completely different thing" because of "territorial disputes". Peter Dickinson of the Atlantic Council wrote that Putin's "dislike of NATO enlargement is real enough, but it has nothing to do with legitimate national security concerns. Instead, Putin objects to NATO because it prevents him from bullying Russia's neighbours".
Since the invasion, calls for Ukrainian NATO membership have grown. On 30 September 2022, Ukraine submitted an application for NATO membership.
According to ''Politico'', NATO members are reluctant to discuss Ukraine's entry because of Putin's "hypersensitivity" on the issue. At NATO's 2023 Vilnius summit it was decided that Ukraine would no longer be required to participate in a Membership Action Plan before joining the alliance.
Georgia
Georgia
Georgia most commonly refers to:
* Georgia (country), a country in the South Caucasus
* Georgia (U.S. state), a state in the southeastern United States
Georgia may also refer to:
People and fictional characters
* Georgia (name), a list of pe ...
moved quickly following the Rose Revolution in 2003 to seek closer ties with NATO (although the previous administration had also indicated that it desired NATO membership a year before the revolution took place). Georgia's northern neighbor,
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
, opposed the closer ties, including those expressed at the
2008 Bucharest summit, where NATO members promised that Georgia would eventually join the organization.
Complications in the relationship between NATO and Georgia includes the presence of Russian military forces in internationally recognized Georgian territory as a result of multiple recent conflicts, like the 2008 Russo-Georgian War over the territories of Abkhazia and South Ossetia, both of which are home to a large number of citizens of Russia. On 3 December 2008, NATO's 26 foreign ministers voted to reject a Membership Action Plan, Membership Action Plan (MAP) to Georgia, arguing that it would antagonize Russia and that Georgia needed to enact more reforms. On 21 November 2011, President of Russia, Russian President Dmitry Medvedev while addressing soldiers in Vladikavkaz near the Georgian border stated that Russia's 2008 invasion had prevented any further NATO enlargement into the former Soviet Union, Soviet sphere.
A 2008 Georgian referendum, nonbinding referendum in 2008 resulted in 77 percent of voters supporting NATO accession. In May 2013, Prime Minister of Georgia, Georgian Prime Minister Bidzina Ivanishvili stated that his goal was to get a
Membership Action Plan (MAP) for his country from NATO in 2014. In June 2014, diplomats from NATO suggested that while a MAP was unlikely, a package of "reinforced cooperation" agreements was a possible compromise. Anders Fogh Rasmussen confirmed that this could include the building of military capabilities and armed forces training.
In September 2019, Russian Foreign Minister Sergey Lavrov said that "NATO approaching our borders is a threat to Russia." He was quoted as saying that if
NATO
The North Atlantic Treaty Organization (NATO ; , OTAN), also called the North Atlantic Alliance, is an intergovernmental organization, intergovernmental Transnationalism, transnational military alliance of 32 Member states of NATO, member s ...
accepts Georgian membership with the article on collective defense covering only Tbilisi-administered territory (i.e., excluding the Georgian territories of Abkhazia and South Ossetia, both of which are currently an List of states with limited recognition, unrecognized breakaway republics supported by Russia), "we will not start a war, but such conduct will undermine our relations with NATO and with countries who are eager to enter the alliance."
On 29 September 2020, NATO Secretary General Jens Stoltenberg called on Georgia to use every opportunity to move closer to the Alliance and speed up preparations for membership. Stoltenberg stressed that earlier that year, the Allies agreed to further strengthen the NATO-Georgia partnership, and that NATO welcomed the progress made by Georgia in carrying out reforms, modernizing its armed forces and strengthening democracy. Georgian President Salome Zourabichvili, who took office in 2018, has conceded that NATO membership might not be possible while Russia occupies Georgian territory, and has sought to focus on European Union membership, for which Georgia–European Union relations, Georgia submitted its application in May 2022.
Membership debates
The Soviet Union was the primary ideological adversary for NATO during the Cold War. Following its dissolution, several states which had maintained neutrality (international relations), neutrality during the Cold War or were
post-Soviet states
The post-Soviet states, also referred to as the former Soviet Union or the former Soviet republics, are the independent sovereign states that emerged/re-emerged from the dissolution of the Soviet Union in 1991. Prior to their independence, they ...
increased their ties with Western institutions; a number of them requested to join NATO. The 2022 Russian invasion of Ukraine reignited debate surrounding NATO membership in several countries.
Austria
Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...
,
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
, Switzerland, and
Malta
Malta, officially the Republic of Malta, is an island country in Southern Europe located in the Mediterranean Sea, between Sicily and North Africa. It consists of an archipelago south of Italy, east of Tunisia, and north of Libya. The two ...
have maintained their Cold War–era neutrality. All are now members of the
Partnership for Peace, and all except Switzerland are now members of the
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
. The defence ministry of Switzerland, which has a Swiss neutrality, long-standing policy of neutrality, initiated a report in May 2022 analyzing various military options, including increased cooperation and joint military exercises with NATO. That month, a poll indicated 33% of Swiss supported NATO membership for Switzerland, and 56% supported increased ties with NATO.
Cyprus
Cyprus (), officially the Republic of Cyprus, is an island country in the eastern Mediterranean Sea. Situated in West Asia, its cultural identity and geopolitical orientation are overwhelmingly Southeast European. Cyprus is the List of isl ...
is also a member state of the European Union, but it is the only one that is neither a full member state nor participates in the Partnership for Peace. Any treaty concerning Cyprus' participation in NATO would likely be blocked by
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
because of the Cyprus dispute.
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
,
Armenia
Armenia, officially the Republic of Armenia, is a landlocked country in the Armenian Highlands of West Asia. It is a part of the Caucasus region and is bordered by Turkey to the west, Georgia (country), Georgia to the north and Azerbaijan to ...
, Belarus, and Kazakhstan are all members of the Collective Security Treaty Organization (CSTO), a post-Soviet alternative military alliance. Azerbaijan was a member of the CSTO but has committed to a policy of neutrality since 1999. In 2000, Russian President
Vladimir Putin
Vladimir Vladimirovich Putin (born 7 October 1952) is a Russian politician and former intelligence officer who has served as President of Russia since 2012, having previously served from 2000 to 2008. Putin also served as Prime Minister of Ru ...
floated the idea of Russia potentially joining NATO. However these prospects went nowhere, and Putin began developing anti-NATO sentiment and espousing hostile views towards NATO from the early 2000s. In 2009, Russian envoy Dmitry Rogozin did not rule out joining NATO at some point, but stated that Russia was currently more interested in leading a coalition as a great power.
Austria
Austria
Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...
was Allied-occupied Austria, occupied by the four victorious Allies of World War II, Allied powers following
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
under the Allied Control Council, similar to Allied-occupied Germany, Germany. During negotiations to end the occupation, which were ongoing at the same time as Germany's, the Soviet Union insisted that the reunified country adopt the model of Swiss neutrality. The US feared that this would encourage
West Germany
West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...
to accept similar Stalin Note, Soviet proposals for neutrality as a condition for German reunification. Shortly after West Germany's accession to NATO, the parties agreed to the Austrian State Treaty in May 1955, which was largely based on the Moscow Memorandum signed the previous month between Austria and the Soviet Union. While the treaty itself did not commit Austria to neutrality, this was subsequently enshrined into Austria's constitution that October with the Declaration of Neutrality. The Declaration prohibits Austria from joining a military alliance, from hosting foreign military bases within its borders, and from participating in a war.
Membership of Austria in the
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
(or its predecessor organizations) was controversial because of the Austrian commitment to neutrality. Austria only joined in 1995 enlargement of the European Union, 1995, together with Sweden and Finland, which had also declared their neutrality in the Cold War. Austria joined NATO's
Partnership for Peace in 1995, and participates in NATO's
Euro-Atlantic Partnership Council
The Euro-Atlantic Partnership Council (EAPC) is a post–Cold War, North Atlantic Treaty Organization (NATO) institution. The EAPC is a multilateral forum created to improve relations between NATO and non-NATO countries in Europe and Central Asi ...
. The Military of Austria, Austrian military also participates in the United Nations Peacekeeping Operations, United Nations peacekeeping operations and has deployments in several countries , including
Kosovo
Kosovo, officially the Republic of Kosovo, is a landlocked country in Southeast Europe with International recognition of Kosovo, partial diplomatic recognition. It is bordered by Albania to the southwest, Montenegro to the west, Serbia to the ...
, Lebanon, and
Bosnia and Herzegovina
Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkans, Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to th ...
, where it has led the Operation Althea, EUFOR mission there since 2009.
Individual politicians from the Austrian People's Party (ÖVP) have supported NATO membership as part of European integration, including the Chancellor from 2000 to 2007, Wolfgang Schüssel and his defense minister, Werner Fasslabend.
The 2022 Russian invasion of Ukraine, and subsequent NATO membership of Finland and Sweden, did lead to additional calls to re-open the issue of neutrality, including from Andreas Khol, the 2016 ÖVP presidential nominee. However, only the NEOS – The New Austria and Liberal Forum, NEOS party, which then held 15 of the 183 seats in the National Council (Austria), National Council, supported a May 2022 open letter asking the government to review its commitment to neutrality, and Chancellor Karl Nehammer, of the ÖVP, has rejected the idea. Membership is not widely popular with the Austrian public. A March 2023 survey found only 21% in favor, with 61% against, a small increase of both 7% in favor and 7% unsure, compared to the last survey 10 months prior.
Cyprus
Prior to gaining its independence in 1960, Cyprus was a crown colony of the United Kingdom and as such the UK's NATO membership also applied to British Cyprus. The Sovereign Base Areas of Akrotiri and Dhekelia in Cyprus remained under British control as a British Overseas Territory following independence. Neighbouring Greece–Turkey relations#Cyprus and the EU, Greece and Turkey competed for influence in the newly independent Cyprus, with intercommunal rivalries and movements for enosis, union with Greece or Taksim (politics), partition and partial union with Turkey. The first Presidents of Cyprus, President of the independent Republic of Cyprus (1960–1977), Archbishop of Cyprus Makarios III, adopted a policy of non-alignment and took part in the 1961 founding meeting of the Non-Aligned Movement in Belgrade.
The 1974
Turkish invasion of Cyprus
The Turkish invasion of Cyprus began on 20 July 1974 and progressed in two phases over the following month. Taking place upon a background of Cypriot intercommunal violence, intercommunal violence between Greek Cypriots, Greek and Turkish Cy ...
and ongoing Cyprus dispute, dispute, in which Turkey continues to occupy Northern Cyprus, complicates Cyprus' relations with NATO. Any treaty concerning Cyprus' participation in NATO, either as a full member, PfP or
Euro-Atlantic Partnership Council
The Euro-Atlantic Partnership Council (EAPC) is a post–Cold War, North Atlantic Treaty Organization (NATO) institution. The EAPC is a multilateral forum created to improve relations between NATO and non-NATO countries in Europe and Central Asi ...
, would likely be vetoed by
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
, a full member of NATO, until the dispute is resolved.
NATO membership for a reunified Cyprus has been proposed as a solution to the question of security guarantees, given that all three of the current guarantors under the Treaty of Guarantee (1960) (Greece, Turkey and the United Kingdom) are already NATO members.
The Parliament of Cyprus voted in February 2011 to apply for membership in the PfP program, but President of Cyprus, President Demetris Christofias vetoed the decision, arguing that it would hamper his attempts to negotiate an end to the Cyprus dispute and demilitarize the island. Nicos Anastasiades, who was 2013 Cypriot presidential election, elected President in 2013, stated that he intended to apply for membership in the PfP program soon after taking over. His foreign minister Nikos Christodoulides later dismissed Cypriot membership of NATO or Partnership for Peace, preferring to keep Cyprus' Foreign relations of Cyprus, foreign and defence affairs within the framework of the EU, i.e. the Common Security and Defence Policy (CSDP). In May 2022, defence minister Charalambos Petrides confirmed that the country would not apply to NATO despite the 2022 Russian invasion of Ukraine, Russian invasion of Ukraine.
After the 2023 Cypriot presidential election, 2023 presidential election, Anastasiades' foreign minister Christodoulides succeeded him as President. In November 2024, Christodoulides reversed his previous stance and revealed a plan to deepen Cyprus' relations with NATO and eventually join as a full member. Under the first phase of the plan, Cyprus would seek to join preparatory organisations linked to NATO, which would require progress in resolving the Cyprus dispute with NATO member Turkey and improvements to European Union–Turkey relations, EU–Turkey relations. Practical steps of the plan include securing a longer-term exemption from the U.S. arms embargo, expanding joint military training opportunities for the Cypriot National Guard at U.S. military academies, and modernisation of Cyprus' defence infrastructure to meet NATO standards. Christodoulides stated that "the U.S. response has been very positive" and that these steps "will ensure that, once all conditions are met, Cyprus can join NATO".
Ireland
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
was Irish neutrality during World War II, neutral during World War II, though the country cooperated with Allied intelligence and permitted the Allies use of Irish airways and ports. Ireland continued its policy of Irish neutrality, military neutrality during the Cold War, and before soldiers in the Irish military, the Defence Forces (Ireland), Defence Forces, can be sent abroad, Irish law requires approval from the government, the Dáil Éireann, and the United Nations, which has been referred to as a "triple lock" on Irish neutrality since the early 2000s. Ireland supplied a small number of troops to the NATO-led International Security Assistance Force (ISAF) in Afghanistan (2001–2014) and supports the ongoing NATO-led Kosovo Force (KFOR).
Ireland joined NATO's
Partnership for Peace (PfP) program and
Euro-Atlantic Partnership Council
The Euro-Atlantic Partnership Council (EAPC) is a post–Cold War, North Atlantic Treaty Organization (NATO) institution. The EAPC is a multilateral forum created to improve relations between NATO and non-NATO countries in Europe and Central Asi ...
(EAPC) in 1999, and participates in the alliance's PfP Planning and Review Process (PARP). This aims to increase the interoperability of the Defence Forces (Ireland), Defence Forces with NATO member states and bring them into line with accepted international standards so as to successfully deploy with other professional military forces on peacekeeping operations overseas. The country most recently renewed their agreement with NATO regarding interoperability in February 2024, with the issues of cybersecurity and the security of submarine communications cable, underseas communication cables in Irish waters being added as additional areas of cooperation.
While there are a number of individual politicians who support Ireland joining NATO, mainly within the center-right Fine Gael party, no major political party in Ireland currently supports full accession to NATO, a reflection on public opinion in the country. Though its stance was softened during the 2024 Irish general election, 2024 election campaign, the Irish republicanism, republican party Sinn Féin has long supported both withdrawal from PfP and passage of a Amendments to the Constitution of Ireland, constitutional amendment to prohibit the country from joining a military alliance like NATO. The Dáil Éireann has considered and defeated such an amendment in April 2019 and in November 2023. While Taoiseach Micheál Martin said in 2022 that Ireland would not need to hold a referendum in order to join NATO, Irish constitutional lawyers have pointed to the precedent set by the 1987 case ''Crotty v. An Taoiseach'' as suggesting it would be necessary, and that any attempt to join NATO without a referendum would likely be legally challenged in the country's courts in a similar way. Former Taoiseach Leo Varadkar has also highlighted the possibility that a United Ireland would likely have to reconsider defense arrangements, namely those with NATO, as the six counties of Northern Ireland are currently part of the alliance.
Polling did show a rise in support for joining NATO following the February 2022 Russian invasion of Ukraine, as a March 2022 poll reported 48% supporting NATO membership and 39% opposing it, while one in August 2022 found 52% in favor of joining and 48% opposed. By June 2023, however, the numbers had returned to prior levels, with around 34% in favour and 38% opposed. Former Secretary General of NATO Anders Fogh Rasmussen said during a visit to the country in 2013 that the "door is open" for Ireland to join NATO at any time.
Kosovo

According to Ministry of Foreign Affairs (Kosovo), Minister of Foreign Affairs Enver Hoxhaj, integration with NATO is a priority for
Kosovo
Kosovo, officially the Republic of Kosovo, is a landlocked country in Southeast Europe with International recognition of Kosovo, partial diplomatic recognition. It is bordered by Albania to the southwest, Montenegro to the west, Serbia to the ...
, which 2008 Kosovo declaration of independence, declared independence from Serbia in 2008. Kosovo submitted an application to join the PfP program in July 2012,
and Hoxhaj stated in 2014 that the country's goal is to be a NATO member by 2022. In December 2018, Prime Minister of Kosovo, Kosovar Prime Minister Ramush Haradinaj stated that Kosovo will apply for NATO membership after the formation of the Kosovo Armed Forces. Kosovo's lack of International recognition of Kosovo, recognition by four Member states of NATO, NATO member states—
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
,
Romania
Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...
,
Spain
Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...
, and
Slovakia
Slovakia, officially the Slovak Republic, is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the west, and the Czech Republic to the northwest. Slovakia's m ...
—could impede its accession.
United Nations membership, which Kosovo does not have, is considered to be necessary for NATO membership.
In February 2022, during the Russian invasion of Ukraine, Minister of Defense Armend Mehaj requested a permanent US military base in the country and an accelerated accession process to the organization, citing an "immediate need to guarantee peace, security and stability in the Western Balkans".
On 3 March 2022, a resolution was passed by Kosovo's Parliament requesting that the government "take all necessary steps to join NATO,
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
, Council of Europe and other international organizations".
Malta
When the North Atlantic Treaty was signed in 1949, the Mediterranean island of
Malta
Malta, officially the Republic of Malta, is an island country in Southern Europe located in the Mediterranean Sea, between Sicily and North Africa. It consists of an archipelago south of Italy, east of Tunisia, and north of Libya. The two ...
was a dependent territory of the United Kingdom, one of the treaty's original signatories. As such, the Crown Colony of Malta shared the UK's international memberships, including NATO. Between 1952 and 1965, the headquarters of the Allied Forces Mediterranean was based in the town of Floriana, just outside Malta's capital of Valletta. When Malta gained independence in 1964, prime minister George Borg Olivier wanted the country to join NATO. Olivier was concerned that the presence of the NATO headquarters in Malta, without the security guarantees that NATO membership entailed, made the country a potential target. However, according to a memorandum he prepared at the time he was discouraged from formally submitting a membership application by Deputy Secretary General of NATO James A. Roberts. It was believed that some NATO members, including the United Kingdom, were opposed to Maltese NATO membership. As a result Olivier considered alternatives, such as seeking associate membership or unilateral security guarantees from NATO, or closing the NATO headquarters in Malta in retaliation. Ultimately, Olivier supported the alliance and signed a defense agreement with the UK for use of Maltese military facilities in exchange for around £2 million a year.
This friendly policy changed in 1971, when Dom Mintoff, of the Labour Party (Malta), Labour Party, was elected as prime minister. Mintoff supported Neutral country, neutrality as his foreign policy, and the position was later enshrined into the country's Constitution of Malta, constitution in 1974 as an amendment to Article 1. The country joined the Non-Aligned Movement in 1979, at the same time when the British Royal Navy left its base at the Malta Dockyard. In 1995, under Prime Minister Eddie Fenech Adami of the Nationalist Party (Malta), Nationalist Party, Malta joined the
Euro-Atlantic Partnership Council
The Euro-Atlantic Partnership Council (EAPC) is a post–Cold War, North Atlantic Treaty Organization (NATO) institution. The EAPC is a multilateral forum created to improve relations between NATO and non-NATO countries in Europe and Central Asi ...
multilateral defense forum and NATO's
Partnership for Peace program. When the Labour Party regained power the following year, however, it withdrew Malta from both organizations. Though the Nationalists resumed the majority in parliament in 1998, Malta didn't rejoin the EAPC and PfP programs again until 2008, after the country had joined the
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
in 2004. Since re-joining, Malta has been building its relations with NATO and getting involved in wider projects including the PfP Planning and Review Process and the NATO Science for Peace and Security Program.
NATO membership is not supported by any of the country's political parties, including neither the governing Labour Party nor the opposition Nationalist Party (Malta), Nationalist Party. NATO's secretary-general Jens Stoltenberg has stated that the alliance fully respects Malta's position of neutrality, and put no pressure for the country to join the alliance.
Polling done by the island-nation's Ministry for Foreign and European Affairs (Malta), Ministry of Foreign Affairs found in February 2022 that 63% of those surveyed supported the island's neutrality, and only 6% opposed the policy, with 14% undecided. A Eurobarometer survey in May 2022 found that 75% of Maltese would however support greater military cooperation within the European Union.
Moldova
Moldova
Moldova, officially the Republic of Moldova, is a Landlocked country, landlocked country in Eastern Europe, with an area of and population of 2.42 million. Moldova is bordered by Romania to the west and Ukraine to the north, east, and south. ...
gained independence in 1991 following the collapse of the Soviet Union. The Constitution of Moldova, country's current constitution was adopted in 1994, and forbids the country from joining a military alliance, but some politicians, such as former Moldovan Minister of Defence Vitalie Marinuța, have suggested joining NATO as part of a larger European integration. Moldova joined NATO's
Partnership for Peace in 1994, and initiated an Individual Partnership Action Plan in 2010.
Moldova also participates in NATO's peacekeeping force in Kosovo.
Following the 2014 Annexation of Crimea by the Russian Federation, annexation of Crimea by Russia, NATO officials warned that
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
Proposed Russian annexation of Transnistria, might seek to annex Transnistria, a breakaway Moldovan region. This separatist issue could preclude Moldova from joining NATO.
The current Prime Minister of Moldova, Dorin Recean, supports
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
membership, but not NATO membership. Moldova's President Maia Sandu stated in January 2023 that there was "serious discussion" about joining "a larger alliance", though she didn't specifically name NATO.
The second largest alliance in the parliament of Moldova, the Electoral Bloc of Communists and Socialists, strongly opposes NATO membership. A poll in December 2018 found that, if given the choice in a referendum, 22% of Moldovans would vote in favor of joining NATO, while 32% would vote against it and 21% would be unsure. Some Moldovan politicians, including former Prime Minister of Moldova, Prime Minister Iurie Leancă, have also supported the idea of Unification of Moldova and Romania, unifying with neighboring Romania, with which Moldova shares a language and much of its history, and a poll in April 2021 found that 43.9% of those surveyed supported that idea.
Romania
Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...
is a current member of both NATO and the European Union.
Serbia
Socialist Federal Republic of Yugoslavia, Yugoslavia's communist government sided with the Eastern Bloc at the beginning of the
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
, but pursued a policy of Neutrality (international relations), neutrality following the Tito–Stalin split in 1948. It was a Yugoslavia and the Non-Aligned Movement, founding member of the Non-Aligned Movement in 1961. Since Breakup of Yugoslavia, that country's dissolution most of its Succession of states, successor states have joined NATO, but the largest of them,
Serbia
, image_flag = Flag of Serbia.svg
, national_motto =
, image_coat = Coat of arms of Serbia.svg
, national_anthem = ()
, image_map =
, map_caption = Location of Serbia (gree ...
, has maintained neutrality.
The NATO intervention in Bosnia and Herzegovina in 1992 against Army of Republika Srpska, Bosnia-Serbian forces and the NATO bombing of Yugoslavia, NATO bombing of targets in Serbia (then part of Serbia and Montenegro, FR Yugoslavia) during the Kosovo War in 1999 resulted in strained relations between Serbia and NATO. After the overthrow of President Slobodan Milošević Serbia wanted to improve its relations with NATO, though membership in the military alliance remained highly controversial among political parties and society. In the years under Prime Minister Zoran Đinđić the country (then Serbia and Montenegro) did not rule out joining NATO, but after Assassination of Zoran Đinđić, Đinđić's assassination in 2003 Serbia increasingly started preferring a course of military neutrality. National Assembly (Serbia), Serbia's Parliament passed a resolution in 2007 which declared Serbia's Neutral country, military neutrality until such time as a referendum could be held on the issue. Relations with NATO were further strained following 2008 Kosovo declaration of independence, Kosovo's declaration of independence in 2008, while it was a United Nations Interim Administration Mission in Kosovo, protectorate of the United Nations with security support from NATO.
Serbia was invited to and joined NATO's
Partnership for Peace program during the
2006 Riga summit, and in 2008 was invited to enter the intensified dialog program whenever the country was ready.
On 1 October 2008, Serbian Defence Minister Dragan Šutanovac signed the Information Exchange Agreement with NATO, one of the prerequisites for fuller membership in the
Partnership for Peace program. In April 2011 Serbia's request for an IPAP was approved by NATO, and Serbia submitted a draft IPAP in May 2013. The agreement was finalized on 15 January 2015. Serbian President Aleksandar Vučić, in office since 2017, reiterated in March 2022 that his government was not interested in NATO membership. A poll that month suggested that 82% of Serbians opposed joining NATO, while only 10% supported the idea. The minor Serbian Renewal Movement, which has two seats in the National Assembly (Serbia), National Assembly, and the Liberal Democratic Party (Serbia), Liberal Democratic Party, which currently has none, remain the most vocal political parties in favor of NATO membership. The Democratic Party (Serbia), Democratic Party abandoned its pro-NATO attitude, claiming the Partnership for Peace is enough.
Serbia maintains Russia–Serbia relations, close relations with Russia, which are due to their shared stances on the Kosovo issue and popular affinity for Russia. Serbia and Belarus are the only European states that refused to impose sanctions on Russia in response to its 2022 Russian invasion of Ukraine, invasion of Ukraine.
Other proposals
Some individuals have proposed expanding NATO outside of Europe, although doing so would require amending Article 10 of the
North Atlantic Treaty
The North Atlantic Treaty, also known as the Washington Treaty, forms the legal basis of, and is implemented by, the North Atlantic Treaty Organization (NATO). The treaty was signed in Washington, D.C., on 4 April 1949.
Background
The treat ...
, which specifically limits new membership to "any other European State in a position to further the principles of this Treaty and to contribute to the security of the North Atlantic area."
Christopher Sands of the Hudson Institute proposed Mexico, Mexican membership of NATO in order to enhance NATO cooperation with Mexico and develop a "North American pillar" for regional security, while Christopher Skaluba and Gabriela Doyle of the Atlantic Council promoted the idea as way to support democracy in Latin America. In June 2013, Colombian President Juan Manuel Santos stated his hope that Colombia's cooperation with NATO could result in NATO membership, though his Foreign Minister, Juan Carlos Pinzón, Juan Carlos Pinzon, quickly clarified that Colombia is not actively seeking NATO membership. In June 2018, Qatar expressed its wish to join NATO, but its application was rejected by NATO. In March 2019, US President Donald Trump made Brazil a major non-NATO ally, and expressed support for the eventual accession of Brazil into NATO. France's Foreign Ministry responded to this by reiterating the limitations of Article 10 on new membership, and suggested that Brazil could instead seek to become a NATO global partners, global partner of NATO, like Colombia.
Several other current NATO global partners have been proposed as candidates for full membership. In 2006, Ivo Daalder, later the US Ambassador to NATO, proposed a "global NATO" that would incorporate democratic states from around the world, including Asia-Pacific partners Australia, New Zealand, Japan, and South Korea, collectively known as the Indo-Pacific Four (IP4), who all signed on as global partners in the 2010s, as well as Brazil, South Africa, and India.
In 2007, then-US presidential candidate Rudy Giuliani suggested including Singapore and Israel, among others. In 2020, Trump stated that Middle Eastern countries should be admitted to NATO. Because of its close ties to Europe, Cape Verde has been suggested as a future member and the government of Cape Verde suggested an interest in joining as recently as 2019.
Internal enlargement is the process of new member states arising from the break-up of or secession from an existing member state. There have been and are a number of List of active separatist movements in Europe, active separatist movements within member states. After a long history of NATO debate in the Scottish National Party, opposition to NATO, the Scottish independence, separatist Scottish National Party agreed at its conference in 2012 that it wished for Scotland to retain its NATO membership were it to become independent from the United Kingdom. In 2014, in the run up to the 2014 Catalan self-determination referendum, self-determination referendum, the Generalitat de Catalunya published a memo suggesting an Catalan independence movement, independent Catalonia would want to keep all of Spain's current foreign relationships, including NATO, though other nations, namely Belgium, have questioned whether quick membership for breakaway regions could encourage secessionist movements elsewhere.
See also
* Enlargement of the European Union
* Withdrawal from NATO
*
Euro-Atlantic Partnership Council
The Euro-Atlantic Partnership Council (EAPC) is a post–Cold War, North Atlantic Treaty Organization (NATO) institution. The EAPC is a multilateral forum created to improve relations between NATO and non-NATO countries in Europe and Central Asi ...
* List of countries in Europe by military expenditures
References
Bibliography
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* Goldgeier, James. "NATO Enlargement and the Problem of Value Complexity." ''Journal of Cold War Studies'' (2020) 22#4 pp 146–174
*
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* Spohr, Kristina. "Precluded or precedent-setting? The 'NATO enlargement question' in the triangular Bonn-Washington-Moscow diplomacy of 1990–1991." ''Journal of Cold War Studies'' 14.4 (2012): 4–54
online
*
* Trachtenberg, Marc.
The United States and the NATO Non-extension Assurances of 1990: New Light on an Old Problem?" ''International Security'' 45:3 (2021): 162–203
The United States and the NATO Non-extension Assurances of 1990: New Light on an Old Problem? an
online commentary on H-DIPLO 2021
*
*
*
*
Further reading
* Goldgeier, James and Joshua Shifrinson, (eds.). ''Evaluating NATO Enlargement: From Cold War Victory to the Russia-Ukraine War.'' (Springer, 2023). ISBN 978303123364
online book review*
* Miles, Simon. 2024. "doi:10.1162/isec a 00477, We All Fall Down: The Dismantling of the Warsaw Pact and the End of the Cold War in Eastern Europe." ''International Security'' 48 (3): 51–85.
*
*
External links
Official NATO enlargement site
{{DEFAULTSORT:Enlargement Of Nato
Enlargement of NATO,
Enlargement of intergovernmental organizations, Nato
Events affected by the Russian invasion of Ukraine